Morris County Average 1999 NATA Modeled Air Concentrations Compared to Health Benchmarks

Pollutant

Modeled
Air Concentration (ug/m3)

Health
Benchmark (ug/m3)

Risk
Ratio

%
Contribution from

Major Sources

Area
Sources

On-road
Mobile Sources

Nonroad
Mobile Sources

Background

Acetaldehyde

1

0.45

3

0.7%

4%

48%

10%

38%

Acrolein

0.09

0.020

4

0.04%

21%

59%

20%

0%

Arsenic Compounds

0.00005

0.00023

0.2

17%

83%

0%

0%

0%

Benzene

1

0.13

9

0.09%

5%

40%

18%

37%

Bis(2-ethylhexyl)phthalate

2

0.42

4

0.02%

0.004%

0%

0%

100%

1,3-Butadiene

0.1

0.033

3

0.002%

2%

31%

20%

48%

Cadmium Compounds

0.00003

0.00024

0.1

8%

92%

0%

0.5%

0%

Carbon Tetrachloride

0.3

0.067

4

0.001%

0.2%

0%

0%

100%

Chloroform

0.08

0.043

1.8

4%

45%

0%

0%

51%

Chromium (hexavalent form)

0.00007

0.000083

0.8

6%

82%

12%

0.7%

0%

1,4-Dichlorobenzene

0.04

0.091

0.4

1%

99%

0%

0%

0%

1,3-Dichloropropene

0.07

0.25

0.3

0%

100%

0%

0%

0%

Diesel Particulate Matter

1

0.0033

442

0%

0%

46%

54%

*

Ethylene Dibromide

0.02

0.0017

15

0.01%

0.007%

0%

0%

100%

Ethylene Dichloride

0.04

0.038

1

0.4%

0.2%

0%

0%

99%

Ethylene Oxide

0.002

0.011

0.2

14%

86%

0%

0%

0%

Formaldehyde

1

0.077

19

0.5%

4%

30%

12%

53%

Methyl Chloride

1

0.56

2

0.007%

0.3%

0%

0%

100%

Naphthalene

0.04

0.029

1.5

0.2%

65%

26%

8%

0%

Nickel Compounds

0.002

0.0064

0.3

2%

97%

2%

0.2%

0%

Perchloroethylene

0.2

0.17

1

0.09%

39%

0%

0%

61%

1,1,2,2-Tetrachloroethane

0.06

0.017

3

0.05%

0.2%

0%

0%

100%

Chemicals with risk ratios greater than or equal to 1 are
in bold.
Risk Ratios in italics are based on noncarcinogenic effects.
The symbol ug/m3 is micrograms per cubic meter,
the amount (in micrograms) of a chemical in a cubic
meter of air. This is also known as a concentration.
* For diesel particulate matter, onroad and nonroad
concentrations include a model-estimated background
concentration.